Responsive website and app?

Question

Marketing

I noticed that they usually make a non-adaptive site, let it be https://www.avito.ru
and have a mobile application. It is clear here that they drive all the traffic into the application in order to monetize there.
But why make a responsive website and mobile app? How did https://youla.ru
For what purpose?
Explain when and why to make a responsive website and app, and when to make a non-responsive website and app.

Answer 1

It is best to always make an adaptive and an application, if necessary (for example, if you have some kind of service, e-commerce, etc., but not when you have a landing page for the sale of one product - this is me about the application).
An adaptive site is made for those who:
1. Fumbled in the browser and got to the site.
2. Just does not want to download the application.
3. Who does not support the application (old OS, device, etc.).
and many more factors.
For example, I don’t download the VK application, because I go there once a year, and the phone’s browser is enough for me.

Answer 2

Because it is cheap in the context of the user and there are users who do not want to install the application, I sold several things there and what now is the application to install?